1. Field of the Invention
The present invention relates to a liquid discharge head cartridge for recording characters, images and the like on a recording sheet or the like by discharging ink or the like.
2. Description of the Related Art
The configurations of ink-jet recording heads for improving the recording speed of an ink-jet recording apparatus have been disclosed as the shapes of ink introducing units of conventional ink-jet recording cartridges, particularly ink-jet recording heads (e.g., Japanese Patent Application Laid-Open (Kokai) No. 2002-137410).
Ink-jet recording heads of this type have a configuration for maintaining an excellent state of contact between a filter and a pressing member contacting the filter in order to stabilize an ink supply property for the ink-jet recording head, because the flow rate of supplied ink is large.
The above-described conventional ink-jet head will now be described with reference to FIGS. 9A–9D.
FIG. 9A is a plan view illustrating an ink introducing unit of an ink-jet recording cartridge. FIGS. 9B–9D are cross-sectional views of the ink introducing unit shown in FIG. 9A.
A cylindrical ink introducing unit 111 incorporates an ink channel 112 for supplying an ink-jet recording head (not shown) with ink, and a filter 113 fixed at one end portion of the ink channel 112. In the ink introducing unit 111, a plurality of struts 116 for supporting the filter 113 at the end portion of the ink channel 112 are provided, in order to prevent the filter 113 from bending toward the ink channel 112.
A projection having a curved surface is provided at a central portion of the filter 113, and a circumferential portion of the filter 113 is flat. As shown in FIG. 9B, after being mounted on one end portion of the ink channel 112, the filter 113 is fixed on the struts 116 provided at circumferential portions of the end portion by heat welding.
As shown in FIGS. 9C and 9D, the central portion of the filter 113 is subjected to a pressing process so as to form a flat contact surface. A flat contact surface ensures excellent contact between the filter 113 and the pressing member 117, regardless of the surface hardness of the pressing member 117.
Recently, ink-jet recording apparatuses have tended to be smaller in size and lower in cost. Thus, reduction in the size of the apparatus' components and in the production cost is important.
One approach to reducing the size of an ink-jet recording apparatus is to reduce the amount of ink removed by recovery processing (i.e., light recovery processing), as well as reducing the space to accommodate removed ink. One approach to reducing production cost is to completely remove recovery processing (hereinafter referred to as “no recovery”).
Recovery processing is performed in order to prevent events like orifices of an ink-jet recording head becoming clogged, or bubbles entering and growing in an ink channel of an ink-jet recording cartridge, where bubble(s) hinder the flow of ink. In particular, in order to remove a bubble from within an ink channel, it is necessary to remove all the ink residing within the ink channel.
In order to achieve the above-described light recovery/no recovery, it is necessary to secure an excellent ink discharge operation without an adverse influence, even if a bubble is present within an ink channel of an ink-jet recording cartridge.
In the above-described conventional ink-jet recording cartridge (for example, refer to Japanese Patent Application Laid-Open Patent No. 2002-137410), recording can be performed with no problems by performing ordinary recovery processing comprising of entirely removing the ink and any bubbles within the ink channel. However, in the conventional ink-jet recording head, when adopting light recovery where light recovery processing is performed only for clogging of an orifice, or no recovery in which no recovery processing is performed, removal of a bubble within the ink channel is not performed. Thus, there the possibility remains that the bubble can block the flow of ink, resulting in decreased recording performance.
In order to prevent blocking of the flow of ink by a bubble, it is necessary to increase the volume of the ink channel and the cross section of the ink channel in a direction perpendicular to the direction of the flow of ink within the ink channel. However, when the diameter of the cross section of the ink channel (i.e., liquid introducing channel) of the ink-jet recording cartridge is simply increased, the positions to provide struts for supporting the filter are limited, resulting in an inability to prevent deformation (e.g., a recess) in the direction of the thickness of the filter.